Check engine light just came on while driving back home to Atlanta from Jacksonville, Fl. I had Advance Auto Parts run a scan and the code came up P0420-Catalyst System Efficiency Below Threshold (Bank 1). They suggested take to dealer to have repaired. A couple of questions.

1.How long can I actually drive the car with this issue? I am going to have it repaired within the next week anyway.
2. Is this normally covered under warranty? Car has close to 89,000 miles. Bought used in '03 with 14,000 miles.

 

I assume you have a V6. The code seems to show that the O2 sensors, before and after theCAT are showing the same values - CAT is not functioning properly. Emissions may have a 5 year/100,000 mile warranty as per government reg.. It looks like you need a new CAT. You should try to find out why the CAT failed and correct that first. Is the car burning oil? Dealer may replace for free but I would do some research first to make sure the dealer is dealing a straight hand.